Metal flashing strip



Sept. 22, 1942. c. H. BUETOW METAL FLASHING STRIP Filed June 1'7, 1940 fnivnior Aiiarneys Patented Sept. 22, 1942 UNITED STATES PATENT OFFICE Claims.

This invention relates to flashing strips for intercepting moisture leakage below vertical joints in masonry wall to prevent seepage of moisture into joints therebelow.

Conventional flashing comprises elongated sheets of metal laid substantially continuously in mortar joints between courses of brick or stone to arrest the flow or seepage of water through masonry Walls either horizontally or vertically. These sheets of flashing are placed along and above an entire cours of bricks or stones before the next course is laid. With flashing of this type a considerable amount of metal is used and it can only be placed in the wall while it is being erected.

It is a general object of my invention to provide metal flashing strip for arresting and carrying off seepage through vertical masonry joints wherein individual flashing element can be used for each vertical joint, thus resulting in a considerable saving of metal between joints and also permitting the placing Of the flashing elements in a previously constructed wall.

Another object of the invention is to provide a flashing strip which includes a valley running from one wall face to the other wherein the valley is lower at one end than the other and wherein means is provided for simply and quickly positioning the strip to insure proper drainage through the valley.

A further object of the invention is to provide a flashingstrip which is conveniently adaptable for use in any type of masonry wall such as in parapet walls and beneath their copings as Well as below masonry window sills or beneath any substantially vertical joint in any masonr structure.

These and other objects and advantages of the invention will more fully appear from the following description made in connection with the accompanying drawing, wherein like reference characters refer to the same parts throughout the views, and, in which:

Fig. 1 is a fragmentary sectional view of a masonry wall taken approximately on the line l-l of Fig. 2;

Fig. 2 is a fragmentary view of a masonry wall section with my improved flashing'strip incorporated therewith;

Fig. 3 is a plan view of the strip; and

Fig. 4 is a perspective view'looking longituditween the upper maincourse 5 and the coping sections is a mortar or other suitable bond 1 and between adjacent end portions of the coping sections 6 is a mortar joint 8. is used moisture seeps down the vertical joints such as the joint 8 and thence down through the mortar or other bonding material through successive vertical joints and across horizontal joints with the result that masonry walls are frequently stained and at points lower down in the main wall where plaster is applied directly to the masonry it also becomes stained, and if sufficient moisture is present the plaster will fall off.

Instead of incorporating a continuous flashing along the course of masonry beneath the coping as has been done heretofore I provide a series of independent flashing strips F for each vertical joint such as the joint 8. This flashing strip comprises an elongated strip of sheet metal whose longitudinal edges 9 are the through wall edges. By the latter term I mean those edges which extend through from one face of the wall to the other; the short end edges l0 and II I designate as the wall face edges. Running longitudinally of the strip and preferably in the center thereof I have provided a valley [2 which is flanked by corrugations providing smaller valleys or grooves [3, the latter at their outer sides having downwardly and outwardly extending flanges l4, and the extreme longitudinal edges 9 of the main strip are bent upwardly, as best shown in Figs. 2 and 4, to provide still another pair of valleys or channels 15. The longitudinal sides of the strip preferably extend downwardly below the lowest point of the main longitudinal valley I 2. Where the sides of the strip extend below the valley I2 any moisture which is in the valley and which might become frozen will tend to press the valley down rather than to force th mortar and coping up in its expansion while freezing. The mortar seldom adheres tightly to the metal flashing and consequently there is a small amount of space on the upper and lower sides of the flashing due to. normal contraction and expansion of the wall, and should the legs of th strip be resting upon the brick, stone or concrete of the course immediately beneath it the expansion induced by freezing of moisture will press the valley down rather than cause the mortar and coping stone to be pushed upwardly.

Referring to Fig. 1, it will be seen that the bottom of the Valle 12 slopes downwardly from right to left in a parapet wall. The left-hand wall face would be the inner face so that moisture seeping downwardly through the coping joint 8 When no flashingtom on an incline.

would be caught in the valley l2 and due to the inclination thereof would carry the moisture to the inner side of the wall where it would drop upon the roof. Of course, in other portions of masonry structures it might be desirable to reverse the position of the flashing strip to carry the moisture to the outside face of the wall as would be the case where th strips were used under the vertical joints in masonry window sills.

In Fig. 2 the inclination of the valley i2 is indicated by-the full line edge of the strip portion which defines the valley when compared with the dotted line I I which is the right-hand or highest strip is shown with a deeper curve than the far end.

In order to insure proper positioningof the in clined valley $2 the longitudinal edges -9 '-of the strip are formed at an angle to the valley bottom. This difference in angular position can be best brought out by considering the longitudinal edges of the strip as being horizontal and the valley bot- Thus'the strip can be placed with its longitudinal edges relatively flat and level and the sloping valley will of necessity be in its correctly inclined position." 7

From the showing of Fig. 2 it will be seen that the main Valley 12 is of greater width than the thickness of the vertical coping joint 8. Thus any moisture seeping down through the joint will be received by the valley and carried off. However, in the event of considerable seepage it is conceivable that some moisture might seep laterallyQwhereupon it would be caught by the small corrugations 13- immediately beside the main valley or by the corrugationsor channels [5 at the longitudinal edges of the flashing strip. These corrugations additionally serve to strengthen the flashing strip and maintain it in its proper shape and position.

In Fig, 1 the'flashing strip is shown as terminating' approximately at the outer face of the ings, it is preferred that the two flashings be of types of metal which will not set up a corrosive action in the presence of moisture. It is preferred 7 that the standard flashing be made of zinc, but

zinc should not be used adjacent copper roof flashing. It is preferred that the two flashings be of similar material.

It is obvious that my flashing element can be incorporated in a masonry wall as the wall is being built. It is also possible to place the flashing units in a previously constructed wall by removing a portion of the bonding material such as mortar from beneath the vertical joint and in the horizontal joint between courses of masonry. The flashing can be slipped into position and fresh mortar used to replace that which was removed.

From theforegoing it will be seen that I have provided a flashing element for through wall flashing of vertical joints and masonry walls which eliminates the need for continuous flashing between courses of masonry and which can be inserted either during wall construction or afterward. It is simple to manufacture and requires no interlock between next adjacent flashing strips as in the case of continuous flashing which is usually made up in sections with their adjacent edges connected and it performs all the functions of a continuous flashing with a considerable saving of metal. The flashing strip is so arranged that it can be quickly and easily set in position with the sloping valley properly disposed, and due to the natural tendency of mortar and similar bonding materials not to adhere closely to smooth metal surfaces and also due to expansion and contraction of material in the wall the moisture will have nearly uninterrupted flow down the sloping 'valley. The result is that walls can be effectively 7 and cheaply constructed with my flashing elements and no seepage is possible through the vertical joints below the flashing. 7 A great advantage of my flashing strip over a conventional continuous flashing is that it does not weaken the bond between the courses of building material since the strip occupies only a short space in the joint horizontally thereof, whereas with continuous flashing there is no mortar bond between the courses above and below the flashing. As a result the wall is weakened and in the case of parapet walls it is dangerous to place scaffold hooks over the top of the walls since there is likelihood that the walls will topple at the joint where the continuous flashing is placed.

Where the flashing is used beneath a stone coping or in walls where large blocks are used my flashing can be of a height which is the same as the thickness of the horizontal mortar joint and in such cases the flashing can be used as a wedge to properly fit the stone before the mortar or cement is filled in. This eliminates the need for the customary wood wedges in wall courseswhere the flashing is used.

It will, of course, be understood that various changes may be made in the form, details, arrangement and proportions of the various parts without departing from the scope of my invention.

What is claimed is: V

1. A through wall vertical joint flashing for masonry walls comprising a sheet of substantially rigid water resistant material having a pair of opposite wall face edges and a pair of through wall edges, and a portion of said sheet having a valley formed therein substantially from one wall face edge to the other, one end of said valley being lower than the other.

2. The structure in claim 1 and said valley having a longitudinal slope substantially from end to end. 1

3. The structure in claim 1 and the through wall edges of said sheet'and the longitudinal bottom portion of said valley lying at an angle to each other. 7 l

4. A through wall vertical joint flashing for masonry walls comprising a sheet of substantially rigid water resistant material having a pair of opposite wall face edges and a pair of through wall edges, a portion of said sheet having a valley formed therein substantially from wall face edge to the other, one end of said valley being lower than the other, and portions of said sheet laterally of said valley comprising valley supportin leg elements.

5. A through wall vertical joint flashing for masonry walls comprising an elongated strip of sheet material, the longitudinal edges thereof constituting through wall edges and the short end edges constituting wall face edges, said strip having longitudinal corrugations formed therein, at least one of said corrugations comprising a valley lower at one end than at the other, and the width of said sheet and its valley being suflicient to bridge a downward continuation of the space in a substantially vertical joint in a masonry wall.

6. In a masonry wall structure, a plurality of building units united by a bonding material to provide substantially vertical and horizontal joints, a plurality of spaced flashing strips embedded in a substantially horizontal joint between certain of said building units, said flashing strips extending transversely substantially from one wall face to another and lying beneath vertical joints in said wall, and said bonding material lying between said spaced flashing strips and also forming an uninterrupted bond between vertically adjacent building units.

7 In a masonry wall structure, a plurality of building units united by a bonding material to provide substantially vertical and horizontal joints, a plurality of spaced flashing strips embedded in a substantially horizontal joint between certain of said building units, said flashing strips extending transversely substantially from one wall face to another and lying beneath vertical joints in said wall, said flashing strips having longitudinal valleys formed therein, and

portions of said strips laterally of said valleys comprising valley supporting elements.

8. The structure in claim '7 and said valleys being sloped substantially throughout the lengths of said strips,

9. A through wall vertical joint fiashingfor masonry walls comprising, an elongated strip of sheet material, the longitudinal edges thereof constituting through wall edges and the short end edges thereof constituting wall face edges said strip having a longitudinal valley therein between said through wall edges, one end of said valley being lower than the other, and the width of said sheet and its valley being suflicient to bridge downward extensions of the space in a substantially vertical joint in a masonry wall.

10. A through wall vertical joint flashing for masonry walls comprising, an elongated strip of sheet material, the longitudinal edges thereof constituting through wall edges and the short end edges thereof constituting wall face edges, said strip having a longitudinal valley therein between said through edges, the width of said sheet and its valley being sufiicient to bridge downward extensions of the space in a substantially vertical joint in a masonry wall, and said valley having a slope longitudinally thereof substantially throughout the length of said strip.

CARL H. BUETOW. 

